Boss 351 Block From Ford Racing

The big-block is dead. We’ve heard from factory sources that the venerable Ford 385-series (429/460/514) crate engines are going to be discontinued, though blocks and heads will continue to be available for the custom builder. The cause? Small-blocks that are smaller, lighter, and pack the same inches and horsepower punch, thanks to major advances in cylinder head and block design. We’re not talking about the modular series of small-blocks—we’re talking about 302/351 Windsor-based engines that will drop into your ’60s and ’70s Mustang/Cougar, Galaxie, or Fairlane. The blocks are from Ford Racing, and the Boss 351 shown here can be built to a staggering 460 inches. With the available superchargers and turbos, you can make virtually any power number you want.

The Boss 351 block will take a 4.155 bore and 4.250 stroke for 461 inches, but that will require some clearancing and a sonic check to be sure the walls are at least 0.200-inch thick.

The iron Boss 351 block shown here has Siamese bores (no coolant passages between them) for additional strength and weighs 205 pounds. There is also an aluminum version that weighs 124 pounds. Both use a 351W timing chain, cover, and oil pump.

Like the Boss 302 and the standard ’85-and-later 302, the Boss 351 has provisions for a factory roller cam and lifters. Also note the thicker bulkhead in the lifter valley.